The accusations come amid increased speculation that the Sadrists could have an increased role in the new parliament, potentially receiving more votes than candidates from the Supreme Islamic Iraqi Council (SIIC) within the Iraqi National Alliance, al-Maliki's main Shiite Muslim competition.

Salah al-Obeidi, a spokesman for the Sadrist group, on Tuesday accused al-Maliki's office of planting rumours of an arrest warrant against al-Sadr that were broadcast on Arabic satellite news stations Monday night.

"We tracked this rumour and found it was issued by the prime minister's office, as were as the sources denying it later," al- Obeidi said.

"Launching a psychological war against the Sadrists at this time aims at reaching two things," al-Obeidi added.

The first, he said, was to create confusion and chaos in the streets ahead of the March 7 parliamentary elections.

The other is "to prevent ... Moqtada al-Sadr from appearing in Kufa mosque, because his presence scares some parties."

Al-Obeidi accused al-Maliki of opening subjects that aim at provoking the Sadrists "because of the sanctity and respect that Iraqis in general, and Sadrists in particular, have for His Eminence."

The prime minister's office denied it had revived talk of executing a 2004 arrest warrant for al-Sadr in connection with the murder of Shiite cleric Abdel-Majid al-Khoei.

That arrest warrant led to clashes at the time between al-Sadr's now largely defunct militia, the Mahdi Army, and US forces in the Iraqi city of al-Najaf, sacred to Shiite Muslims.

Al-Maliki's office said the Sadrists' claims had "electoral motives."

On Monday, al-Sadr called on Iraqis to participate in the elections.

"I was, and still am, against the electoral process under the oppressive occupier," he said in a statement.

But, he said, "it has become necessary to go through this political experiment. The free believers' success would provide safety for Iraq and Iraqis."

"This may be the way to get the occupiers out, as well as the terrorists, militias and security companies," al-Sadr said.